The current trend of engine manufacturers is to increase the engine compression ratio in order to obtain increased power together with a reduction in fuel consumption. This requires a gasoline with a very high anti-knock tendency.
Gasoline is a mixture of hydrocarbons with a tremendously variable tendency for knocking. To avoid this problem and consequently raise the octane number as close as possible to 100 (in the case of mixtures of purely isooctane gasolines), anti-knock compounds such as tetraethyl-lead and tetramethyl-lead have been used.
Although these products have proved to have the best performance with regard to their cost/effectiveness ratio, they have generated very important atmospheric pollution problems.
For this reason, the legislation of most industrial countries envisage an even greater reduction of lead levels in gasoline, with total elimination foreseen by the beginning of next decade.
Batches of non-lead gasoline sold so far on the market have not managed to satisfy users because of their very low anti-knock, tendency. On the other hand, obtaining up-graded gasoline using cracking and similar processes would result in price increases due to the large investments required, which could hardly be absorbed by small refineries.
On the other hand, catalytic filters are very expensive in proportion to their short life, reduce engine power, and at the same time considerably increase fuel consumption.
However, this invention will allow up-graded gasoline, as required by the market, to be produced by a simple method and low cost.